Here's my response to another poster... Try thinking about it this way... It doesn't take much for your head to bleed; it also bleeds a lot even from small cuts. If a person like Chanyoung, someone who doesn't fight back, gets thrown off balance, they will essentially leave their fate up to gravity. Hyunjin, who is strong, but has a smaller build than Chanyoung, lunged to catch his boyfriend. Lunging can also throw you off balance, especially when it's an impulsive movement. So, we have dead weight Chanyoung being caught by disrupted center-of-gravity Hyunjin right in front of a brick wall. And, with both of Hyunjin's arms around Chanyoung, he couldn't do anything to break his momentum or stop himself from colliding into an immovable object. That type of impact would easily lead to a wound, but even without the blood, we should be concerned about the possibility of Hyunjin getting a concussion.
Here's my response to another poster... Try thinking about it this way... It doesn't take much for your head to bleed; it also bleeds a lot even from small cuts. If a person like Chanyoung, someone who doesn't fight back, gets thrown off balance, they will essentially leave their fate up to gravity. Hyunjin, who is strong, but has a smaller build than Chanyoung, lunged to catch his boyfriend. Lunging can also throw you off balance, especially when it's an impulsive movement. So, we have dead weight Chanyoung being caught by disrupted center-of-gravity Hyunjin right in front of a brick wall. And, with both of Hyunjin's arms around Chanyoung, he couldn't do anything to break his momentum or stop himself from colliding into an immovable object. That type of impact would easily lead to a wound, but even without the blood, we should be concerned about the possibility of Hyunjin getting a concussion.